Bump Binutils to 2.36.1

Signed-off-by: Christoph Muellner <cmuellner@linux.com>

.gitmodules

 [submodule "riscv-binutils"]
 	path = riscv-binutils
 	url = ../riscv-binutils-gdb.git
-	branch = riscv-binutils-2.35
+	branch = riscv-binutils-2.36.1
 [submodule "riscv-gcc"]
 	path = riscv-gcc
 	url = ../riscv-gcc.git